From owner-freebsd-current Thu Sep 30 14:43:44 1999 Delivered-To: freebsd-current@freebsd.org Received: from wall.polstra.com (rtrwan160.accessone.com [206.213.115.74]) by hub.freebsd.org (Postfix) with ESMTP id C289E1570A for ; Thu, 30 Sep 1999 14:43:42 -0700 (PDT) (envelope-from jdp@polstra.com) Received: from vashon.polstra.com (vashon.polstra.com [206.213.73.13]) by wall.polstra.com (8.9.3/8.9.3) with ESMTP id OAA23844; Thu, 30 Sep 1999 14:43:41 -0700 (PDT) (envelope-from jdp@polstra.com) Received: (from jdp@localhost) by vashon.polstra.com (8.9.3/8.9.1) id OAA26474; Thu, 30 Sep 1999 14:43:41 -0700 (PDT) (envelope-from jdp@polstra.com) Message-ID: X-Mailer: XFMail 1.3 [p0] on FreeBSD X-Priority: 3 (Normal) Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 8bit MIME-Version: 1.0 In-Reply-To: <19990930162834.C20978@nonpc.cs.rice.edu> Date: Thu, 30 Sep 1999 14:43:41 -0700 (PDT) Organization: Polstra & Co., Inc. From: John Polstra To: Alan Cox Subject: Re: Now that sigcontext is gone ... Cc: current@freebsd.org Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG Alan Cox wrote: > /* kludge to pass faulting virtual address to sendsig */ > frame->tf_err = eva; > > return((rv == KERN_PROTECTION_FAILURE) ? SIGBUS : SIGSEGV); > } > > Up until this point, frame->tf_err tells me details about the page > fault, such as whether it was a read or a write access. I'd really > like that information to make it out to user-level in addition > to the faulting address. In other words, we should find another > way to pass the faulting address to sendsig than by overwriting > frame->tf_err. Sounds reasonable to me. > P.S. This also reminds me that FreeBSD is non-standard relative > to Linux and all of the major vender commercial Unices in that a disallowed > access, such as a write to a read-only region of memory, generates > a SIGBUS rather than a SIGSEGV. Yes, this even violates the 1996 POSIX spec. John --- John Polstra jdp@polstra.com John D. Polstra & Co., Inc. Seattle, Washington USA "No matter how cynical I get, I just can't keep up." -- Nora Ephron To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message